Two new triterpene rhamnosides from Euphorbia dracunculoides Lam. (June 2015) - Wang, Li
Graphical abstract: Highlights: Two new triterpene saponins were isolated from Euphorbia dracunculoides Lam. The new compounds are the first reports of taraxerene-type triterpene rhamnosides. Four known compounds were isolated from E. dracunculoides for the first time. The structures of new compounds were determined by spectroscopic methods and hydrolysis. Abstract: Two new triterpene rhamnosides, 3 β - O -[ α -l -(2′, 3′, 4′- O -triacetyl)-rhamnopyranosyl]-aleuritolic acid (1 ), and 3 β - O -[α-l -(2′, 3′- O -diacetyl)-rhamnopyranosyl]-aleuritolic acid (2 ), together with four known triterpenoids (3 –6 ) were isolated from the petroleum ether fraction of the 70% aqueous acetone extract of the aerial parts of E. dracunculoides Lam. Their structures were elucidated by means of extensive spectroscopic analysis, acid hydrolysis, and comparison with data reported in the literatures. Among them, compounds 1 and 2 are the first examples of taraxerene-type triterpene rhamnosides, and compounds 3 –6 were isolated from this plant for the first time.